/Engine/Source/Runtime/MovieScene/Public/Channels/MovieSceneChannelData.h
Attempt to find a key at a given time and tolerance
The index of the key closest to InTime and within InTolerance, or INDEX_NONE
int32 FindKey ( [FFrameNumber](API\Runtime\Core\Misc\FFrameNumber) InTime, [FFrameNumber](API\Runtime\Core\Misc\FFrameNumber) InTolerance )